PPM & PPB - Scientific Vocabulary

Interactive Course Summary

Trace Concentration Metrics (PPM and PPB) — Parts per million ($\text{ppm}$) and parts per billion ($\text{ppb}$) express highly dilute solute concentrations as mass-to-mass or mass-to-volume ratios scaled by factors of $10^6$ and $10^9$, respectively. These standardized metrics are necessary for quantitative environmental toxicology assay interpretations.